1. Field of the Invention
This invention relates to a method of manufacturing a polyamine composition from yeast somatic components efficiently and in volume. In detail, it relates to a method of manufacturing a polyamine composition, wherein after digesting yeast somatic components with nuclease or hydrolyzing them with alkali, polyamine is recovered. When manufacturing a polyamine composition from yeast somatic components, by applying the method of this invention, the recovery of polyamine can be improved.
2. Description of the Related Art
A polyamine is a general term for straight chain aliphatic hydrocarbon containing more than two primary amino groups, and as typical polyamines, putrescine, spermidine and spermine can be mentioned. As polyamines' physiological functions, (1) cell proliferation action, (2) cell differentiation accelerating action, (3) an immune essential factor, (4) antiallergic action, (5) protein synthesis acceleration action, (6) structural stabilization by interaction with nucleic acid, (7) enzyme activation regulating action, etc. are known. Recently, many reports have been made that orally taken polyamine accelerates proliferation and differentiation of mucosal cells of the alimentary canal (O. Peulen et al., Arch. Physiol. Biochem., vol.106, pp. 46-55, 1998; W. P. Deloyer et al., Arch. Physiol., Biochem., vol.104, pp. 163-172, 1996; M. Kaouass et al., Dig., Dis. Sci., vol. 41, pp.1434-1444, 1996; E. Harada et al., Comp. Biochem. Physiol., vol.109A, pp.667-673, 1994; G. Capano et al., J. Pediatr. Gastroenterol. Nutr. vol.19, pp.34-42, 1994; G. E. Wild et al., Biol. Neonate, vol.63, pp.246-257, 1993; Buts J. -P. et al., Digestive Diseases and Science, vol.38, p.1091, 1993; Dufour, C. et al., Gastroenterology, vol.95, p.112, 1988).
According to these reports, physiological effects of spermidine and spermine were examined and it was also made clear that spermine has a stronger action than does spermidine to accelerate the alimentary canal to mature. Further, it was reported that orally taken polyamine is quickly absorbed into the body and taken up and utilized by tissues. It was also reported that spermidine and spermine are absorbed more quickly than putrecine (Bardocz, S. et al., J. Nutr. Biochem., vol.4, p.66, 1993).
As examples of using polyamine for food, konnyaku (a jelly-like food made from the starch of devil's tongue) to which spermidine and spermine are added to reduce a smell peculiar to konnyaku and which does not have a bad effect if it is cooked with other foods (Japanese Patent Laid-open No.1994-38690) and a polyamine-mixed nutritional composition to which polyamine is mixed to accelerate protein absorption for the purpose of maintaining satisfactory growth and health conditions (Japanese Patent Laid-open No.1994-305956) and others have been proposed. In addition, as examples of using polyamine as medicines, a method of stopping gastric acid secretion and a composition for intake for the purpose of stopping gastric acid secretion (Japanese Patent Laid-open No.1983-131914) and immune activator (Japanese Patent Laid-open No.1984-98015 and Japanese Patent Laid-open No.1990-223514) and others have been Proposed.
Incidentally, it is known that meats and fermented foods such as cheese and miso (soybean paste) contain more polyamine than do milk and vegetables (Bardocz, S. et al., J. Nutr. Biochem., vol.4, p.66, 1993; Polyamine Society 12th Meeting for Reading Research Papers Lectures Outline, p.4, 1995). Consequently, the amount of polyamine contained in nutritional compositions of infant formula and others, of which milk is the main ingredient, is very small. Additionally, it was reported that human milk contained a relatively large amount of polyamine (Japanese Journal of Pediatric Gastroenterology and Nutrition, vol.1.9, no.2, pp.115-121, 1995) and it can be said that it is preferable from a physiological point of view to enrich polyamine in nutritional compositions with a low polyamine content.
Further, as a nutritional composition with high polyamine content, proteolytic milk has been introduced by Buts and others (Buts, J. P. et al., J. Pediatr. Gastroenterol. Nutr., vol.21, p.44, 1995), but polyamine contained in this proteolytic milk is polyamine derived from natural enzymes used for proteolysis and it is not intended as enrichment of polyamine.
Moreover, a method of manufacturing polyamine from yeast and a nutritional composition to which polyamine manufactured by this method is mixed have been proposed (Japanese Patent Laid-open No.1998-52291). In this method, polyamine without an offensive smell and taste can be manufactured by treating yeast under acidic conditions. However, under acidic conditions, because a part of polyamine precipitates together with a high molecular-weight substance, all the polyamine contained in yeast could not be recovered. Additionally, a part of polyamine is bound in vivo with a high molecular-weight substance, not all polyamine could be recovered simply by performing fractionation.